What is the Conversions API (CAPI)?
The Conversions API is how conversion tracking keeps working when ad blockers, iOS privacy and consent banners break the browser pixel. Here is what it is, how it works, and the simplest way to run it on Shopify.
The Conversions API (CAPI) is a server-to-server connection that sends conversion events directly from your server to an ad platform, separate from the browser pixel. Meta and Pinterest both call theirs the Conversions API, TikTok calls its the Events API, and the umbrella for all of these server-side methods is server-side tracking. Because the event comes from your server, ad blockers and iOS limits cannot stop it, so platforms receive more complete data. On Shopify, TrackBee runs it across every channel in about 5 minutes with no code, and enriches every event with first-party data first.
What is the Conversions API?
The Conversions API, often shortened to CAPI, lets your server send conversion events straight to an ad platform, instead of relying on a tracking script in the shopper's browser. A browser pixel like the Meta Pixel fires on the visitor's device, which is exactly where ad blockers, Safari and iOS restrictions, and declined cookie consent stop a large share of events from ever arriving. The Conversions API moves that step to a server you control, which those browser-level blockers cannot reach.
Every major ad platform has its own server-side method, and the names differ. Meta and Pinterest both call theirs the Conversions API. TikTok calls its the Events API. Google is the exception: it has no product called a Conversions API, so you send conversions to Google Ads server-side through the Google Ads API (moving to Google's Data Manager API), and Enhanced Conversions is a separate feature that enriches each conversion with hashed first-party data so more of them match. GA4 has its Measurement Protocol. In each case your server posts the event directly to the platform, so measurement keeps working when the browser path breaks, and you can attach richer first-party data to each event.
These server-side methods are what server-side tracking is built on. The Conversions API is not a replacement for your pixel, it runs alongside it. For the wider picture and how the pieces fit together, see our full server-side tracking guide.
The browser pixel vs the Conversions API
A browser pixel only records a sale if it loads and fires in the shopper's browser. Often it does not, and the sale still happens without the data reaching your platforms. Four things cause most of the loss.
Ad blockers
Browser extensions and privacy modes block tracking scripts outright, so the pixel never fires.
iOS and privacy limits
Apple's tracking prevention and app-level privacy controls cap cookies and strip identifiers, breaking browser-based matching.
Consent banners
When a shopper declines or ignores cookie consent, the browser pixel is not allowed to run.
Pixel failures
Slow connections, script errors, early tab closes and custom checkouts all cause events to drop silently.
Add it up and a standard browser pixel typically misses around 30 to 60 percent of conversions. The Conversions API recovers those events by sending them from your server, so your platforms optimise and report on complete data instead of a partial picture.
Same store, same sales. The difference is how many of them reach the platform. The Conversions API sends the events the browser drops, straight from your server.
Server-side conversions, platform by platform
Each platform has its own server-side method. The name changes, the principle does not: your server posts the event directly, and you can enrich it with first-party data first.
Meta Conversions API
Sends purchase and funnel events server-side and deduplicates them against the Meta Pixel using a shared event ID. Richer events lift match quality, so more conversions match and Meta's automation, including Advantage+ and the Andromeda retrieval engine, has a stronger signal to work with.
Google Ads (server-side)
Google has no product called a Conversions API. You send conversions to Google Ads server-side through the Google Ads API, and Enhanced Conversions enriches each one with hashed first-party data (email, phone, address) so Google matches more of them and Smart Bidding bids on accurate signals. Enhanced Conversions is the enrichment, not the connection itself.
TikTok Events API
TikTok's server-to-server connection, the direct equivalent of Meta's Conversions API. Paired with the TikTok Pixel and deduplicated, it gives TikTok fuller conversion data.
Pinterest Conversions API
Reports conversions to Pinterest directly from your server, independent of the browser tag, so Pinterest optimises on complete data.
GA4 Measurement Protocol
GA4's server-side method for sending events to Google Analytics 4 from your server. It augments the GA4 tag rather than replacing it, so your analytics stay more complete and consistent with what your ad platforms see.
Klaviyo server-side events
Server-side capture ties cart and browse events to a profile, so Klaviyo flows fire even for anonymous and cross-device shoppers the browser would miss.
How the Conversions API works, done properly
Posting an event server-side is the foundation. The setups that actually move your results go two steps further.
Server-to-server delivery
The event is sent from your server straight to the platform's API, so ad blockers, iOS limits and consent banners cannot silently drop it. This is the part that recovers the conversions the browser pixel loses.
Event deduplication
The pixel and the Conversions API often send the same conversion twice. A shared event ID lets the platform recognise the pair and count it once, so your numbers do not inflate and bidding learns from the truth.
First-party enrichment
Each event is enriched with first-party data (hashed email and phone, click IDs, and product, cart and order context) before it is sent. Richer events raise match quality, so more conversions get matched and used.
A weak setup just moves a thin event to a server and calls it done. A strong one dedupes cleanly and enriches every event first, which is where the Conversions API turns into better ad efficiency.
How TrackBee runs the Conversions API on Shopify
TrackBee is a Shopify app that installs one-click and is live in about 5 minutes, with no Google Tag Manager and no code. It sends your conversions server-side to every channel you use, through each platform's own method (the Conversions API for Meta and Pinterest, the Events API for TikTok, the Google Ads API for Google, and more), recovers the conversions your browser pixels miss, and enriches every event with first-party data before sending it. Deduplication against your existing pixels is built in, and persistent cross-device profiles are on by default on every plan.
Pricing is flat from €79/mo, with all channels included and no per-channel fees. TrackBee Insights, the AI analyst that lets you ask your cross-platform ad data in plain English inside Claude and ChatGPT, is an optional €19.99/mo on top.
- Meta
- TikTok
- GA4 & Klaviyo
- Plus ChatGPT Ads, Microsoft Ads and more
Browser pixel vs Conversions API
| Browser pixel | Conversions API | |
|---|---|---|
| Where it fires | In the shopper's browser | On your server |
| Blocked by ad blockers | Yes, the event is lost | No, blockers cannot reach the server |
| Affected by iOS and consent limits | Heavily | Far less, sent server-side |
| First-party enrichment | Limited to what the browser holds | Full: hashed email, click IDs, cart and order context |
| Typical conversion coverage | Misses around 30 to 60 percent | Recovers the events the pixel drops |
| Best practice | Run both and deduplicate: keep the pixel's browser context and add the server's coverage. | |
Verified July 2026. The pixel and the Conversions API are complementary, not either-or. Most stores run both with deduplication so each conversion is counted once.
The Conversions API, answered
What is the Conversions API (CAPI)?
The Conversions API is a server-to-server connection that lets an ad platform receive conversion events directly from your server, separate from the browser pixel. Meta and Pinterest call theirs the Conversions API and TikTok calls its the Events API. Because the event comes from your server, ad blockers and iOS privacy limits cannot stop it, so the platform receives more complete, more matchable data.
What is the difference between the Conversions API and the pixel?
The pixel fires in the shopper's browser, where ad blockers, iOS limits and declined consent stop a large share of events. The Conversions API sends the same event from your server, which those browser-level blockers cannot reach. Most stores run both and deduplicate, keeping the pixel's browser context and adding the server's coverage.
Is the Conversions API the same as server-side tracking?
They are closely related. Server-side tracking is the outcome, capturing and sending conversion events from a server instead of the browser. The Conversions API is the connection each platform gives you to do that. In practice, a good server-side tracking setup uses the Conversions API for every channel and enriches each event with first-party data first.
What is the Meta Conversions API?
The Meta Conversions API is Meta's version of CAPI. It sends purchase and funnel events from your server to Meta and deduplicates them against the Meta Pixel using a shared event ID. Richer, server-side events raise match quality, so more conversions match and Meta's automation, including Advantage+ and the Andromeda retrieval engine, has a stronger signal to optimise on.
Do I need the Conversions API?
For any Shopify store running paid ads or Klaviyo, it is close to essential. A browser pixel alone misses around 30 to 60 percent of conversions, so your platforms optimise on incomplete data. The Conversions API recovers those events and lets you enrich them, which usually pays for itself in better ad efficiency and recovered email revenue.
How do I set up the Conversions API on Shopify?
You can build it yourself for each platform, or use a purpose-built app. TrackBee is the turnkey route: it installs in about 5 minutes with no code or Google Tag Manager, sends your conversions server-side to Meta, Google, TikTok, Pinterest, GA4 & Klaviyo, enriches every event with first-party data, and handles deduplication automatically. Pricing is flat from €79/mo.
Run server-side conversions on Shopify, without the build
Recover the conversions your pixels miss and send Meta, Google, TikTok, Pinterest, GA4 & Klaviyo the complete, enriched data they need. Flat from €79/mo, live in about 5 minutes.
Last updated: July 2026